A thermoresponsive Poly(N-isopropylacrylamide) (PNIPAAm)-modified nylon membrane was fabricated via hydrothermal route. Combining rough structure, proper pore size, and thermoresponsive wettability, the membrane can separate at least 16 types of stabilized oil-in-water and water-in-oil emulsions at different temperatures. Below the LCST (ca. 25 °C), the material exhibits hydrophilicity and underwater superoleophobicity, which can be used for the separation of various kinds of oil-in-water emulsions. Above the LCST (ca. 45 °C), the membrane shows the opposite property with high hydrophobicity and superoleophilicity, and it can then separate stabilized water-in-oil emulsions. The material exhibits excellent recyclability and high separation efficiency for various kinds of emulsions and the hydrothermal method is facile and low-cost. The membrane shows good potential in real situations such as on-demand oil-spill cleanup, industrial wastewater treatment, remote operation of oil/water emulsion separation units, and fuel purification.

New hyperbranched poly(trimellitic anhydride-triethylene glycol) ester epoxy (HTTE) is synthesized and used to toughen diglycidyl ether of bisphenol A (DGEBA) 4,4(-diaminodiphenylmethane (DDM) resin system. The effects of content and generation number of HTTE on the performance of the cured systems are studied in detail. The impact strength is improved 2--7 times for HTTE/ DGEBA blends compared with that of the unmodified system. Scanning electron microscopy (SEM) of fracture surface shows cavitations at center and fibrous yielding phenomenon at edge which indicated that the particle cavitations, shear yield deformation, and in situ toughness mechanism are the main toughening mechanisms. The dynamic mechanical thermal analyzer (DMA) analyses suggest that phase separation occurred as interpenetrating polymer networks (IPNs) for the HTTE/DGEBA amine systems. The IPN maintains transparency and shows higher modulus than the neat epoxy. The glass transition temperature (T g ) decreases to some extent compared with the neat epoxy. The T g increases with increase in the generation number from first to third of HTTE and the concentrations of hard segment. The HTTE leads to a small decrease in thermal stability with the increasing content from TGA analysis. The thermal stability increases with increase in the generation number from first to third. Moreover, HTTE promotes char formation in the HTTE/DGEBA blends. The increase in thermal properties from first to third generation number is attributed to the increase in the molar mass and intramolecular hydrogen bridges, the increasing interaction of the HTTE/ DGEBA IPNs, and the increasing crosslinking density due to the availability of a greater number of end hydroxyl and end epoxide functions.

We have successfully fabricated sandwich structural Ag3PO4 nanoparticle/polydopamine/Al2O3 porous small balls (APPAOs) by a facile homogeneous precipitation method, which exhibit a natural light catalysis capacity to degrade different kinds of water pollutants including industrial dyes and agricultural pesticides. The porous Al2O3 provides the substrate to form the Ag3PO4/Al2O3 heterojunction, as well as increases the specific surface area (SSA) of the Ag3PO4 nanoparticle, thus greatly enhancing the photocatalytic capacity. Polydopamine (PDA) plays the role of adhesive between Al2O3 substrate and Ag3PO4 nanoparticle, aiming to stabilize the synthesized APPAO catalyst. A part of Ag3PO4 is reduced by PDA and transformed into a Ag nanosphere, which further increases SSA and enhances the catalytic ability of the material by the plasmonic effect. Further study shows that there is a dynamic process between catalysis and adsorption/desorption equilibrium; i.e., with the catalysis going ahead, the adsorption/desorption equilibrium accordingly shifts thus thoroughly treating the pollutants. In addition, the superhydrophilic surface provides the APPAO with an excellent antioil property, which greatly reduces secondary pollution, and the small ball structure makes the material easy to use and recycle. Because of its excellent reusability, mild catalytic conditions, and ease of use, the APPAO has great potential to be used in the field of low-cost practical wastewater treatment.

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A novel multicomponent system has been constructed through the combination of Hantzsch reaction and reversible addition–fragmentation chain transfer (RAFT) polymerization in a one-pot manner. Compared to traditional stepwise methods, this one-pot system exhibits much more advantages to facilely and efficiently prepare well-defined poly(1,4-dihydropyridine)s (poly(1,4-DHP)s). A series of poly(1,4-DHP) derivatives have also been successfully prepared through this Hantzsch–RAFT system using different aldehydes as reactants, suggesting this system is a general and versatile approach to prepare well-defined functional polymers with 1,4-DHPs as side groups. Since 1,4-DHP derivatives are an important class of bioactive molecules in the pharmaceutical field, this simple method to prepare poly(1,4-DHP)s might have potential to prepare related functional polymers for biological and pharmaceutical applications.